How it does this is not completely understood, but one study showed that it reduces the production of the hunger hormone ghrelin (9).

One study showed that people taking capsaicin ate less food throughout the day than those who didn't take any. Specifically, those taking capsaicin supplements ate 10% less, while those who drank a capsaicin-containing beverage ate 16% less (10).

People in the same study also reported feeling fuller, while eating fewer calories (10).

Summary: The capsaicin in cayenne peppers may help reduce your hunger, helping you eat less throughout the day.